A prior art stethoscope receiver is illustrated in FIG. 1 and an exploded perspective view of the prior art stethoscope receiver is shown in FIG. 2. In this prior art, the receiver 1 has threaded tubes at an upper and a lower ends 11 and 12 which are screwed to an upper cover 2 and a listening disk 3. A lateral wall of the receiver 1 has a connecting hole 13 for being inserted to a transducer. A rear end of the transducer 4 is connected to a connector 5. A rear end of the connector 5 may be a sound receiving device 51 having one tube or two tubes. The medical member holds the upper cover 2 and the listening disk 3 will contact the stomach or breast of the patient. Since the listening disk 3 often contacts patients so that the use of the listening disk 3 must be confined. That is, after a time period, the listening disk 3 must be detached for sterilization, even the listening disk 3 will be deserted and a new one is updated. Thereby, many listening disks 3 are necessary. Moreover, the listening disks for adults and children are different and thus medical members must update the listening disks frequently.
In the prior art, if it is desired to separate the listening disk from the receiver 1. It is necessary to rotate the listening disk 3 clockwise so that the listening disk is separated from the threaded tube. When it is desired to reinstall the listening disk 3, a screw hole 31 at a center of the listening disk 3 must be aligned to the threaded tube 12 so as to rotate counterclockwise for fixing. However, to align the listening disk 3 with the threaded tube 12 is difficult and it is often that the listening disk 3 can not be screwed into the lowest portion of the threaded tube 12. As a result, it is possible that the threaded tube 12 will be broken if the listening disk 3 is screwed into the threaded tube in force. Thus, the listening disk 3 is difficult to draw out. Thereby, the listening disk 3 must be drawn out to screw into the threaded tube 12 again. Thus, the operation is tedious and inconvenient.
Next, the upper cover 2 and listening disk 3 are screwed. The upper cover dose not contact the patients and thus it can be used many times and no problem of infection occurs. Moreover, the prior art upper cover has no indication so that the medical members often take an unwanted stethoscope receiver by mistake.